Applications of gel electrophoresis in the determination of protein-low M-r substances and protein protein interactions

Electrophoretic techniques may be exploited to assess the interactions between test proteins and either low or high M(r) components in several ways. Stable complexes may be migrated as such, and only the difference in size and/or surface charge between reactants and complexes determines the extent of resolution. Either pre-run tagging (by radioactive labeling) or post-run detection (by functional recognition) may be applied to the identification of either component. For loosely interacting species, the available approaches include chemical reaction before the run (by affinity labeling or cross-linking), and affinity detection after the run (by ligand blotting). Copyright (C) 1998 Elsevier Science B.V.